The architect of the US financial conglomerate Citigroup has stunned the banking industry by calling for a separation of high street banks from their casino investment banking arms.

Sandy Weill, who was an influential voice in encouraging the US to repeal the Glass-Steagall Act which had prevented co-ownership of high street and investment banks, appeared to indicate that the types of financial firm he had helped to create should now be broken up.

"What we should probably do is go and split up investment banking from banking," he told CNBC. "Have banks be deposit takers, have banks make commercial loans and real estate loans. And have banks do something that is not going to risk the taxpayer dollars, that's not going to be too big to fail," he said.

Glass-Steagall had been a key piece of legislation following the Great Depression to keep the two main elements of banking apart but came to end in 1999, allowing Citigroup to merge with Travelers and create a financial services giant.

Weill left Citigroup before it was rescued by US taxpayers during the crisis and acknowledged the current scandals hitting the industry were having a long-term impact. "Our world hates bankers ... There is such a feeling among people, among regulators, among the political system all over the world against the banking system, and I don't think that is going to change so soon," he said.

Weill was among those to lobby for Glass-Steagall to be changed, a feat of which he was proud. The New York Times reported that his portrait had hung his in office, with the words "The Shatterer of Glass-Steagall" engraved beneath it.

But it now the subject of debate on both sides of Atlantic following the taxpayer bailouts of banks during the 2008 crisis. In the US the Volcker rule has stopped banks engaging in some riskier activities but does not call for a full separation while in the UK the Independent Commission on Banking, chaired by Sir John Vickers, is requiring a ring fence to be erected between investment banks and high street banks, rather than total separation.

Now 79, Weill also lamented the state of the industry. "It is really sad what is happening, and it's sad for young people. This was an industry that attracted a lot of really terrific people," he said.